A single cell protection input high voltage protection method and system

Abstract

The present invention discloses a single-cell protection input high-voltage protection method and system, the system includes a sampling circuit, a power conversion circuit, a reference circuit, an overcharge and over-discharge comparator and a logic processing circuit, the power conversion circuit converts the cell into a low voltage under high voltage conditions, keeps the cell voltage equal to the cell voltage under normal voltage conditions, the full voltage range does not affect the normal operation of the chip, and the converted low-voltage power supply current path has a resistor current limiting, and at the same time adds a high-voltage abnormal shutdown function for the cell to protect the safety of the subsequent load. Most of the internal circuits in the system can adopt a low-voltage design, which greatly reduces the chip area, reduces costs, and simplifies the design scheme. There is no resistor current limiting in the power supply current path between the low-voltage power supply and the cell, and when the cell voltage is normal, the low-voltage power supply has no voltage loss, which will not affect the index characteristics of the cell under low voltage. The system adds an abnormal high-voltage shutdown function to prevent damage to the subsequent load.

Description

Technical Field

[0001] The present invention belongs to the technical field of battery protection, and relates to a single-cell protection input high-voltage protection method and system. Background Art

[0002] With the development of lithium batteries, the capacity of battery cells is getting larger and larger, which also leads to the emergence of fast charging solutions to solve the problem of slow charging speed.

[0003] Today's fast charging solutions generally increase the charging voltage and charging power. This charging method may cause high voltage on a single battery cell. The traditional design uses a low-voltage design, which cannot ensure that the chip continues to work under high voltage, resulting in chip damage. Therefore, the input end of the single-cell protection chip needs to be able to withstand high voltage continuously. If all high-voltage devices are selected inside the chip, the chip area will be large, the cost will be high, and the design will be complex. If a diode clamp is used internally, it is necessary to increase the resistance to current limiting, and there will be voltage loss, which will cause some of the chip's indicators to deteriorate, especially when the battery cell is at low voltage. The impact is more serious. Summary of the invention

[0004] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art and to provide a single-cell protection input high voltage protection method and system to solve the problem that the traditional single-cell protection circuit input high voltage protection scheme has the problem that the power conversion circuit generates a low-voltage power supply and the current path between the battery cell has resistor current limiting, and when the battery cell voltage is normal, the low-voltage power supply has no voltage loss, which affects the chip working characteristics.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A single-cell protection input high-voltage protection system comprises a cell and a charger connected in parallel; the positive electrode of the cell is connected to a sampling circuit, and the negative electrode of the sampling circuit is connected to the negative electrode of the cell;

[0007] A first branch is provided on the connection circuit between the battery cell and the sampling circuit, the first branch is connected to a power conversion circuit, and a power output end of the power conversion circuit is simultaneously connected to a reference circuit, an overcharge and overdischarge comparator, and a logic processing circuit;

[0008] The signal output end of the sampling circuit is connected to the overcharge and overdischarge comparator, the signal output end of the reference circuit is connected to the signal input end of the overcharge and overdischarge comparator, and the output end of the overcharge and overdischarge comparator is connected to the input end of the logic processing circuit; the signal output end of the power conversion circuit is connected to the input end of the logic processing circuit; the signal output end of the logic processing circuit is connected to the connector drive circuit, and the drive circuit is connected to the discharge tube and the charging tube at the same time, and the other ends of the discharge tube and the charging tube are connected to the negative pole of the battery cell.

[0009] A further improvement of the present invention is:

[0010] Preferably, the power conversion circuit generates a current path between the low-voltage power supply and the battery cell without resistance current limiting.

[0011] Preferably, the device is replaceable with a load.

[0012] Preferably, the power conversion circuit includes a high-voltage tube, a resistor and a Schmitt.

[0013] Preferably, the high pressure pipe PM 301 and high pressure pipe PM 302 The source is connected to the battery cell, and the high-voltage tube PM 301 and high pressure pipe PM 302 The gates of the high-voltage tube PM are connected together. 301 Drain, high-voltage tube PM 301 Grid, high voltage tube NM 301 The gate and resistor R 301 One end of the resistor R 301 The other end of the Zener tube D 301 The negative pole of Zener D 301 The positive pole of the high-voltage pipe PM is grounded; 302 The drain and resistor R 302 Connection, high pressure pipe PM 302 The drain of the high-voltage tube PM 303 The gate is connected to the resistor R 302 The other end of the high-voltage pipe PM is grounded; 303 The source and high voltage tube NM 301 The drain of the battery is connected to the high-voltage tube PM 303 The drain and high-voltage tube NM 301 The source of the high-voltage tube PM is connected to the output terminal VDD; 304 The source is connected to the battery cell, and the high-voltage tube PM 304 The drain and resistor R 303 and Schmidt S. 301 The input is connected to the resistor R 303 The other end of the Schmidt 301 The output is a high voltage signal HOV.

[0014] A protection method based on the above-mentioned single-cell protection input high-voltage protection system,

[0015] When continuous high voltage appears in the battery cell, the power conversion circuit outputs low-voltage power to the reference circuit, overcharge and over-discharge comparator and logic processing circuit; the power conversion circuit also generates an abnormal high-voltage signal HOV to the logic processing circuit, and the logic processing circuit generates a discharge tube enable signal and a charging tube enable signal. The discharge tube enable signal turns off the discharge tube, and the charging tube enable signal turns off the charging tube, thereby cutting off the discharge and charging paths at the same time.

[0016] Preferably, when the battery cell voltage returns to normal, the abnormal high-voltage signal generated by the power conversion circuit is input to the logic processing circuit, and the logic processing circuit generates a discharge tube enable signal and a charging tube enable signal. The discharge tube enable signal opens the discharge tube through the drive circuit, and the charging tube enable signal opens the charging tube through the drive circuit, thereby opening the discharge and charging paths.

[0017] Preferably, when the discharge tube and the charging tube are turned off, the discharge tube enable signal and the charging tube enable signal are at a low level.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] The present invention discloses a single-cell protection input high-voltage protection system, which includes a sampling circuit, a power conversion circuit, a reference circuit, an overcharge and over-discharge comparator, and a logic processing circuit. The power conversion circuit converts the cell into a low voltage under high voltage conditions, and keeps the cell voltage equal to the cell voltage under normal voltage conditions. The full voltage range does not affect the normal operation of the chip, and the converted low-voltage power supply current path has a resistor current limiting function, while adding a high-voltage abnormal shutdown function for the cell to protect the safety of the subsequent load. Most of the internal circuits in the system can adopt a low-voltage design, which greatly reduces the chip area, reduces costs, and simplifies the design scheme. There is no resistor current limiting in the power supply current path between the low-voltage power supply and the cell, and when the cell voltage is normal, the low-voltage power supply has no voltage loss, which will not affect the index characteristics of the cell under low voltage. The system adds an abnormal high-voltage shutdown function to prevent damage to the subsequent load.

[0020] The present invention also discloses a protection method based on a single-cell protection input high-voltage protection system. When the cell has a continuous high voltage, the power conversion circuit always outputs a low-voltage power supply to power the reference circuit, the overcharge and overdischarge comparator, and the logic processing circuit, so as to protect the reference circuit, the overcharge and overdischarge comparator, and the logic processing circuit from being damaged by the high voltage. The abnormal high-voltage signal generated at the same time is used to drive the circuit to turn off the external discharge tube and the charging tube through the discharge tube enable signal and the charging tube enable signal generated by the logic processing circuit, and cut off the discharge and charging paths. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is the traditional solution of power conversion circuit 1;

[0022] Figure 2 It is the traditional solution of power conversion circuit 2;

[0023] Figure 3 This is a system block diagram of the single-cell protection input high-voltage resistance solution of the present invention;

[0024] Figure 4The present invention is an exemplary method flow chart of a single-cell protection input high voltage withstand solution according to an embodiment of the present invention.

[0025] Figure 5 It is a specific embodiment of the power conversion circuit in the present invention;

[0026] Figure 6 It is a traditional low-voltage structure for single-cell protection;

[0027] Figure 7 It is the sampling circuit implementation structure of the present invention;

[0028] Figure 8 This is the driving circuit implementation structure of the present invention.

[0029] Among them: 101 - sampling circuit; 102 - power conversion circuit; 103 - reference circuit; 104 - overcharge and overdischarge comparator; 105 - logic processing circuit; 106 - driving circuit. DETAILED DESCRIPTION

[0030] The present invention is further described in detail below in conjunction with the accompanying drawings:

[0031] In the description of the present invention, it should be noted that the orientations or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention; the terms "first", "second", and "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance; in addition, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal communication of two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0032] like Figure 1As shown, the conventional scheme 1 of the power conversion circuit 102 uses a resistor R101 and a Zener diode D101 to generate a low-voltage power supply VDD. When the cell BAT voltage VCC is continuously high, the low-voltage power supply VDD is the breakdown voltage of the Zener diode D101, which can protect the subsequent low-voltage circuit; when the cell BAT voltage is normal, the low-voltage power supply VDD is the cell BAT voltage VCC. The current path between the low-voltage power supply VDD and the cell BAT voltage VCC is limited by the resistor R101, which protects the Zener diode D101 from damage, but reduces the current capacity and anti-interference ability of the low-voltage power supply VDD.

[0033] like Figure 2 As shown, the traditional solution 2 of the power conversion circuit 102 adds a high-voltage tube NM101 to solve the problem of resistance current limiting in the current path. However, when the battery cell BAT voltage VCC is normal, the generated low-voltage power supply VDD has a VGS loss of the high-voltage tube NM101, resulting in the problem that the internal circuit does not work well when the battery cell BAT voltage VCC is low.

[0034] One embodiment of the present invention discloses a single-cell input high voltage protection system, such as Figure 3 As shown, the invention comprises a sampling circuit 101 , a power conversion circuit 102 , a reference circuit 103 , an overcharge and overdischarge comparator 104 , a logic processing circuit 105 and a driving circuit 106 .

[0035] Specifically, the charger supplies power to the load and the battery cell BAT, and correspondingly, the charger, the battery cell BAT and the load are in a parallel relationship; a sampling circuit 101 is connected in parallel between the battery cell BAT and the charger, and a first branch connected to the power conversion circuit 102 is provided on the connection line between the positive electrode of the battery cell BAT and the sampling circuit 101, and a second branch is provided on the first branch, and the second branch is connected to the drive circuit 106; the other end of the sampling circuit 101 is connected to the negative electrode of the battery cell BAT, and the negative electrode of the drive circuit 106 is connected to the negative electrode of BAT through the discharge tube NM1 and the charging tube NM2. This structure enables the voltage VCC of the battery cell BAT to power the sampling circuit 101 and the drive circuit 106.

[0036] The power input terminal of the power conversion circuit 102 is the first branch. The power conversion circuit 102 is provided with three low-voltage power supply VDD output terminals. The three low-voltage power supplies are respectively connected to the reference circuit 103, the overcharge and overdischarge comparator 104 and the logic processing circuit 105.

[0037] Specifically, the sampling circuit 101 is connected to the battery cell BAT to generate a sampling signal; the power conversion circuit 102 is used to generate a low-voltage power supply VDD and a battery abnormal high-voltage signal HOV; the reference circuit 103 is used to generate reference voltages VREF1 and VREF2; the overcharge and over-discharge comparator 104 is used to generate an overcharge signal OVP and an over-discharge signal UVP; the logic processing circuit 105 is used to generate a discharge tube enable signal DFET and a charging tube enable signal CFET; the drive circuit 106 is used to control the discharge tube NM1 to open and close and the charging tube NM2 to open and close.

[0038] The sampling circuit 101 generates a sampling signal VB by sampling from the battery cell BAT, and the sampling signal VB is input to the overcharge and overdischarge comparator 104. The reference circuit 103 generates reference voltages VREF1 and VREF2, which are transmitted to the overcharge and overdischarge comparator 104; the overcharge and overdischarge comparator generates a process signal OVP or an overdischarge signal UVP, which is transmitted to the logic processing circuit 105.

[0039] VDD is a continuous output voltage. As long as the battery cell BAT is connected, VDD will output voltage. HOV will output a high level HOV only when the battery cell BAT voltage is higher than a certain value (the threshold set by the power conversion circuit 102). During normal operation, the HOV output by the power conversion circuit is a low level.

[0040] The sampling circuit 101 is connected to the battery cell BAT to generate a sampling signal VB. The sampling signal VB and the reference voltages VREF1 and VREF2 generated by the reference circuit 103 output corresponding overcharge signals OVP and overdischarge signals UVP through the overcharge and overdischarge comparator 104. The power conversion circuit 102 generates a low-voltage power supply VDD to power the reference circuit 103, the overcharge and overdischarge comparator 104 and the logic processing circuit 105, and generates an abnormal high-voltage signal HOV at the same time. The overcharge signal OVP, the overdischarge signal UVP and the abnormal high-voltage signal HOV are output through the logic processing circuit 105 as a discharge tube enable signal DFET or a charging tube enable signal CFET. Specifically, the overcharge signal OVP sets the charging tube enable signal CFET to a low level through the logic processing circuit 105, and sets the low-level charging tube enable signal CFET is input to the driving circuit 106, and the driving circuit 106 further drives the charging tube NM2 to turn on and work; the over-discharge signal UVP sets the discharge tube enable signal DFET to a low level through the logic processing circuit 105, and inputs the low-level discharge tube enable signal DFET to the driving circuit 106, and the driving circuit 106 further drives the discharge tube NM1 to turn on and work; the abnormal high-voltage signal HOV passes through the logic processing circuit 105 to set the charging tube enable signal CFET and the discharge tube enable signal DFET to a low level at the same time; the discharge tube enable signal DFET and the charging tube enable signal CFET respectively control the discharge tube NM1 to turn on and off and the charging tube NM2 to turn on and off through the driving circuit 106; the sampling circuit 101 and the driving circuit 106 are powered by the voltage VCC of the battery cell BAT.

[0041] When the battery cell BAT has a continuous high voltage, the power conversion circuit 102 continuously outputs the low voltage power supply VDD to power the reference circuit 103, the overcharge and overdischarge comparator 104 and the logic processing circuit 105, so as to protect the reference circuit 103, the overcharge and overdischarge comparator 104 and the logic processing circuit 105 from being damaged by the high voltage. At the same time, the abnormal high voltage signal HOV passes through the discharge tube enable signal DFET and the charging tube enable signal CFET generated by the logic processing circuit 105, and finally through the driving circuit 106, the external discharge tube NM1 and the charging tube NM2 are turned off at the same time, and the discharge and charging paths are cut off at the same time. The power conversion circuit 102 generates a current path between the low voltage power supply and the battery cell BAT without resistance current limiting, and when the voltage of the battery cell BAT is normal, the low voltage power supply has no voltage loss.

[0042] When the cell BAT voltage returns to normal, the abnormal high-voltage signal HOV generated by the power conversion circuit 102 passes through the discharge tube enable signal DFET and the charging tube enable signal CFET generated by the logic processing circuit 105, and finally reopens the external discharge tube NM1 and the charging tube NM2 through the driving circuit 106, that is, reopens the discharge and charging paths.

[0043] like Figure 4As shown, an exemplary method flow chart of a single-cell protection input high-voltage resistance solution according to an embodiment of the present invention detects that the cell BAT voltage VCC becomes abnormally high, reduces the output of the low-voltage power supply VDD, and turns off the charging tube NM2 and the discharging tube NM1, that is, shuts off the charging and discharging path function to protect the subsequent load from damage.

[0044] The working principle of the present invention is:

[0045] The sampling circuit is used to generate a sampling signal. The sampling signal and the reference circuit generate a reference voltage which is connected to the overcharge and overdischarge comparator. The corresponding overcharge signal and overdischarge signal are output by comparing the sampling signal and the reference voltage. The power conversion circuit is used to generate a low-voltage power supply to power the reference circuit, the overcharge and overdischarge comparator and the logic processing circuit, and generate an abnormal high-voltage signal at the same time. The overcharge signal, the overdischarge signal and the abnormal high-voltage signal are connected to the logic processing circuit to output the discharge tube enable signal and the charging tube enable signal. The discharge tube enable signal and the charging tube enable signal are connected to the drive circuit to respectively control the discharge tube to be turned on and off and the charging tube to be turned on and off. The sampling circuit and the drive circuit are powered by the voltage of the battery cell.

[0046] When the battery cell has continuous high voltage, the power conversion circuit will always output low voltage power to power the reference circuit, overcharge and overdischarge comparator and logic processing circuit, protecting the reference circuit, overcharge and overdischarge comparator and logic processing circuit from damage due to high voltage. At the same time, the abnormal high voltage signal generated by the logic processing circuit generates a discharge tube enable signal and a charging tube enable signal to drive the circuit to turn off the external discharge tube and charging tube, and cut off the discharge and charging paths.

[0047] The following is further described in conjunction with specific embodiments:

[0048] like Figure 5 FIG. 1 is a specific embodiment of the power conversion circuit 102 of the present invention. 301 and PM 302 The source is connected to VCC, the high voltage tube PM 301 and PM 302 The gates of the high-voltage tube PM are connected together. 301 The drain, gate and resistor R 301 And high pressure pipe NM 301 The gate is connected to the resistor R 301 The other end of the Zener tube D 301 The negative pole of the Zener is connected to 301 The positive pole of the high-voltage pipe PM is grounded; 302 The drain and resistor R 301 And high pressure pipe PM 302 and high pressure pipe PM 303 The gate is connected to the resistor R 302The other end of the high-voltage pipe PM is grounded; 303 The source and high voltage tube NM 301 The drain is connected to VCC, the high-voltage tube PM 303 The drain and high-voltage tube NM 301 The source of the high-voltage tube PM is connected to VDD; 304 The source is connected to VCC, the high voltage tube PM 304 The drain and resistor R 303 and Schmidt S. 301 The input is connected to the resistor R 303 The other end of the Schmidt 301 The output is HOV.

[0049] The working process of this circuit is: when the battery cell BAT voltage VCC is normal, the Zener tube D 301 No current, high voltage tube NM 301 The gate voltage is VCC, and the high-voltage tube PM 301 and PM 302 The resistor R forms a current mirror 302 The voltage drop is 0V, that is, the high-voltage tube PM 303 and PM 304 The gate is 0V, and the low voltage power supply VDD is supplied by the high voltage tube PM. 303 Output, low voltage power supply VDD and cell BAT voltage VCC are equal, even if the cell BAT voltage VCC is very low, the internal operation of the chip will not be affected, and the abnormal high voltage signal HOV is generated by Schmidt S 301 The output is low level; when the cell BAT voltage VCC continues to be high, the current limiting resistor R 301 and Zener D 301 Generate current, and at the same time the high-voltage tube PM 301 and PM 302 The resistor R forms a current mirror 302 The pressure drop causes the high pressure pipe PM 303 and PM 304 Shutdown, the low voltage power supply VDD is powered by the high voltage tube NM 301 The low voltage power supply VDD voltage is a VGS voltage drop from the battery cell BAT voltage VCC, which will not affect the normal operation of the chip. The abnormal high voltage signal HOV is generated by Schmidt S 301 The output is high level, which is ultimately used to shut down the charge and discharge path.

[0050] like Figure 6 As shown, the single cell protection traditional low voltage implementation structure. 401 and R 402The conventional sampling circuit 201 is formed to output the sampling signal VB; the reference circuit 103 outputs the reference signals VREF1 and VREF2; the comparator OV and the comparator UV form an overcharge and overdischarge comparator 104, the positive input terminal of the comparator OV is the sampling signal VB, the negative input terminal is the reference signal VREF1, and the overcharge signal OVP is output; the negative input terminal of the comparator UV is the sampling signal VB, the positive input terminal is the reference signal VREF2, and the overdischarge signal UVP is output; the timers TIMER1 and TIMER2 form a logic processing circuit 105, the timer TI The input end of MER1 is the overcharge signal OVP, and the output end is the charging tube enable signal CFET. The input end of the timer TIMER2 is the over-discharge signal UVP, and the output end is the discharge tube enable signal DFET. The charging tube driver and the discharge tube driver form a driving circuit 206. The input end of the charging tube driver is the charging tube enable signal CFET, and the output end is CHC. The input end of the discharge tube driver is the discharge tube enable signal DFET, and the output end is DHC. The sampling circuit 201, the reference circuit 103, the over-charge and over-discharge comparator 104, the logic processing circuit 105 and the driving circuit 206 are powered by VCC. Therefore, VCC can only be input with a low-voltage power supply, and the reliability is poor.

[0051] Figure 6 The reference circuit 103, overcharge and overdischarge comparator 104, and logic processing circuit 105 transmitted in the invention can be directly used in the reference circuit 103, overcharge and overdischarge comparator 104, and logic processing circuit 105 of the present invention. The sampling circuit 201 and the driving circuit 206 can only be used in the traditional low-voltage single-cell protection structure.

[0052] The working process of the circuit is as follows: when the VCC voltage is too high, the sampling signal VB output by the sampling circuit 201 increases and exceeds the reference signal VREF1, the overcharge signal OVP output by the comparator OV becomes high, and the charging tube enable signal CFET becomes low after the timer TIMER1 is completed, and finally the charging tube is driven to make CHC low, thereby shutting off the charging path; when the VCC voltage is too low, the sampling signal VB output by the sampling circuit 201 becomes low and lower than the reference signal VREF2, the over-discharge signal UVP output by the comparator UV becomes high, and the discharge tube enable signal DFET becomes low after the timer TIMER2 is completed, and finally the discharge tube is driven to make DHC low, thereby shutting off the discharge path.

[0053] like Figure 7 As shown, the sampling circuit 101 in the present invention can be implemented by adding a low-voltage clamping circuit at the output end VB of the sampling circuit 201 in the low-voltage single-cell protection structure, and the addition of the low-voltage clamping circuit protects the subsequent overcharge and overdischarge comparator 104 from being damaged due to VCC becoming a high voltage.

[0054] like Figure 8As shown, the drive circuit 106 in the present invention implements the structure. The drive circuit 206 in the low-voltage single-cell protection structure can be used to connect the corresponding charging tube drive and discharge tube drive after the two input ports CFET and DFET are respectively connected in series with the level conversion circuit. The logic processing circuit 105 outputs the charging tube enable signal CFET, which passes through the level conversion circuit and then passes through the charging tube drive to ensure that the charging and discharging tubes can be normally turned on or off after VCC becomes high voltage; similarly, the logic processing circuit 105 outputs the discharge tube enable signal DFET, which passes through the level conversion circuit and then passes through the discharge tube drive to ensure that the discharge tube can be normally turned on or off after VCC becomes high voltage.

[0055] The power conversion circuit 102 in the present invention not only solves the problem of resistance current limiting in the current path between the low-voltage power supply VDD and the battery cell BAT voltage VCC in the traditional solution, but also solves the problem of poor working characteristics of the traditional solution under the low voltage of the battery cell BAT voltage VCC, and at the same time adds the function of shutting off the charging and discharging path at abnormal high voltage to protect the subsequent load from damage.

[0056] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A single cell protection input high voltage protection system, characterized in that: It comprises a battery cell and a charger connected in parallel; the positive electrode of the battery cell is connected to a sampling circuit (101), and the negative electrode of the sampling circuit (101) is connected to the negative electrode of the battery cell; A first branch is provided on the connection circuit between the battery cell and the sampling circuit (101), the first branch is connected to the power conversion circuit (102), and the power output end of the power conversion circuit (102) is simultaneously connected to the reference circuit (103), the overcharge and overdischarge comparator (104), and the logic processing circuit (105); The signal output end of the sampling circuit (101) is connected to the overcharge and overdischarge comparator (104), the signal output end of the reference circuit (103) is connected to the signal input end of the overcharge and overdischarge comparator (104), and the output end of the overcharge and overdischarge comparator (104) is connected to the input end of the logic processing circuit (105); the signal output end of the power conversion circuit (102) is connected to the input end of the logic processing circuit (105); the signal output end of the logic processing circuit (105) is connected to the drive circuit (106), and the drive circuit (106) is simultaneously connected to the discharge tube and the charging tube, and the other ends of the discharge tube and the charging tube are both connected to the negative electrode of the battery cell; There is no resistance in the path from the cell input pin VCC to the low voltage power supply VDD generated by the power conversion circuit (102), and there is no current limiting function; The power conversion circuit (102) includes a high-voltage tube, a resistor and a Schmitt; When a continuous high voltage appears in the battery cell, the power conversion circuit (102) outputs a low voltage power supply to the reference circuit (103), the overcharge and overdischarge comparator (104) and the logic processing circuit (105); the power conversion circuit (102) simultaneously generates an abnormal high voltage signal HOV to the logic processing circuit (105); the logic processing circuit (105) generates a discharge tube enable signal and a charging tube enable signal; the discharge tube enable signal turns off the discharge tube, and the charging tube enable signal turns off the charging tube, thereby cutting off the discharge and charging paths at the same time.

2. A single cell protection input high voltage protection system according to claim 1, characterized in that: The charger is replaced by the load.

3. A single-cell protection input high-voltage protection system according to claim 1, characterized in that: High pressure pipe PM 301 and high pressure pipe PM 302 The source is connected to the battery cell, and the high-voltage tube PM 301 and high pressure pipe PM 302 The gates of the high-voltage tube PM are connected together; 301 Drain, high-voltage tube PM 301 The gate and high voltage tube PM 302 The gate and resistor R 301 One end of the high pressure pipe is connected to NM 301 The gate and R 301 The other end of the high pressure pipe is connected to NM 301 The gate voltage is VCC, and the high-voltage tube PM 304 The gate is 0V, the resistor R 301 The other end of the Zener tube D 301 The negative pole of Zener D 301 The positive pole of the high-voltage pipe PM is grounded; 302 The drain and resistor R 302 Connection, high pressure pipe PM 302 The drain of the high-voltage tube PM 303 The gate is connected to the resistor R 302 The other end of the high-voltage pipe PM is grounded; 303 The source and high voltage tube NM 301 The drain of the battery is connected to the high-voltage tube PM 303 The drain and high-voltage tube NM 301 The source of the high-voltage tube PM is connected to the output terminal VDD; 304 The source is connected to the cell, and the high-voltage tube PM 304 The drain and resistor R 303 and Schmidt S. 301 The input is connected to the resistor R 303 The other end of the Schmidt 301 The output is a high voltage signal HOV.

4. A protection method based on the single-cell protection input high-voltage protection system according to claim 1, characterized in that: When a continuous high voltage appears in the battery cell, the power conversion circuit (102) outputs a low voltage power supply to the reference circuit (103), the overcharge and overdischarge comparator (104) and the logic processing circuit (105); the power conversion circuit (102) simultaneously generates an abnormal high voltage signal HOV to the logic processing circuit (105); the logic processing circuit (105) generates a discharge tube enable signal and a charging tube enable signal; the discharge tube enable signal turns off the discharge tube, and the charging tube enable signal turns off the charging tube, thereby cutting off the discharge and charging paths at the same time.

5. The protection method of the single-cell protection input high-voltage protection system according to claim 4, characterized in that: When the cell voltage returns to normal, the abnormal high voltage signal generated by the power conversion circuit (102) is input to the logic processing circuit (105), and the logic processing circuit (105) generates a discharge tube enable signal and a charging tube enable signal. The discharge tube enable signal is passed through the drive circuit (106) to open the discharge tube, and the charging tube enable signal is passed through the drive circuit (106) to open the charging tube, thereby opening the discharge and charging paths.

6. The protection method of the single-cell protection input high-voltage protection system according to claim 5, characterized in that: When the discharge tube and the charging tube are turned off, the discharge tube enable signal and the charging tube enable signal are at a low level.

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